Early on in the process I believe they noted that they would work on making it so you could change your companions class (kind of like was available in DOS2), but from the sounds of it that will not end up making the game.
I can't say that is a surprise given that a lot of the characters class seems to be very much tied into who they are.
Still strikes me as odd they didn't end up making a companion for every class and that Druid seems like it will be making two appearances.
